Lessons Learned From the Introduction of Inactivated Poliovirus Vaccine in Bangladesh

Vaccine supply chain coordination using blockchain and artificial intelligence technologies

Currently, the global spread of COVID-19 is taking a heavy toll on the lives of the global population. There is an urgent need to improve and strengthen the coordination of vaccine supply chains in response to this severe pandemic. In this study, we consider a vaccine supply chain based on a combination of artificial intelligence and blockchain technologies and model the supply chain as a two-player dynamic game with inventory level as the dynamic equation of the system. The study focuses on the applicability and effectiveness of the two technologies in the vaccine supply chain and provides management insights. The impact of the application of the technologies on environmental performance is also considered in the model. We also examine factors such as the number of people vaccinated, positive and side effects of vaccines, vaccine decay rate, revenue-sharing/cost-sharing ratio, and commission ratio. The results are as follows: the correlation between the difficulty in obtaining certified vaccines and the profit of a vaccine manufacturer is not monotonous; the vaccine manufacturer is more sensitive to changes in the vaccine attenuation rate. The study's major conclusions are as follows: First, the vaccine supply chain should estimate the level of consumers' difficulty in obtaining a certified vaccine source and the magnitude of the production planning and demand forecasting error terms before adopting the two technologies. Second, the application of artificial intelligence (AI) technology is meaningful in the vaccine supply chain when the error terms satisfy a particular interval condition.

One Full or Two Fractional Doses of Inactivated Poliovirus Vaccine for Catch-up Vaccination in Older Infants: A Randomized Clinical Trial in Bangladesh

BACKGROUND

The polio eradication endgame called for the removal of trivalent oral poliovirus vaccine (OPV) and introduction of bivalent (types 1 and 3) OPV and inactivated poliovirus vaccine (IPV). However, supply shortages have delayed IPV administration to tens of millions of infants, and immunogenicity data are currently lacking to guide catch-up vaccination policies.

METHODS

We conducted an open-label randomized clinical trial assessing 2 interventions, full or fractional-dose IPV (fIPV, one-fifth of IPV), administered at age 9-13 months with a second dose given 2 months later. Serum was collected at days 0, 60, 67, and 90 to assess seroconversion, priming, and antibody titer. None received IPV or poliovirus type 2-containing vaccines before enrolment.

RESULTS

A single fIPV dose at age 9-13 months yielded 75% (95% confidence interval [CI], 6%-82%) seroconversion against type 2, whereas 2 fIPV doses resulted in 100% seroconversion compared with 94% (95% CI, 89%-97%) after a single full dose (P < .001). Two doses of IPV resulted in 100% seroconversion.

CONCLUSIONS

Our study confirmed increased IPV immunogenicity when administered at an older age, likely due to reduced interference from maternally derived antibodies. Either 1 full dose of IPV or 2 doses of fIPV could be used to vaccinate missed cohorts, 2 fIPV doses being antigen sparing and more immunogenic.

CLINICAL TRIAL REGISTRATION

NCT03890497.

Factors associated with the utilization of inactivated polio vaccine among children aged 12 to 23 months in Kalungu District, Uganda

Uganda officially introduced the inactivated polio vaccine (IPV) in May 2016 as part of the polio eradication strategy and integrated it into its routine immunization programme in addition to the oral polio vaccine. The current coverage stands at 60% as of July 2017. We therefore aimed to determine factors associated with the uptake of IPV among children in Kalungu District so as to inform the implementation of the vaccine policy. A community-based cross-sectional study was conducted among caregivers of 406 eligible children aged 12-23 months through multi-stage systematic sampling and a standardized semi-structured questionnaire. Nine key informant interviews were conducted through purposive selection of health care providers and members of Village Health Teams (VHTs) based on their expertize. Modified Poisson regression and thematic content analysis were used to determine factors significant to IPV uptake among children. 71% of sampled children aged 12-23 months had received IPV in Kalungu District. The survey found that being encouraged by health workers and VHTs was significant to children's uptake of IPV (Adjusted PR 1.24, 95% CI; 1.22-3.47). Distance to the immunization point (Adjusted PR 0.32,95% CI; 0.16-0.62) and caregiver's education level (Adjusted PR 1.16,95% CI; 1.05-2.22) were also associated with IPV uptake. Qualitative findings from health workers and VHT members further confirmed the perception that distance to the immunization post was important, and VHTs also stated that being encouraged by health workers was critical to IPV uptake. The current prevalence of IPV uptake among children aged 12-23 months in Kalungu is 71%, higher than the last reported national coverage (60%), though still below the recommended national coverage of 95%. Efforts should be focused on sensitization of caregivers through health workers and VHTs. Immunization outreach should be strengthened so as to bring services closer to patients.

Overview of rabies post-exposure prophylaxis access, procurement and distribution in selected countries in Asia and Africa, 2017-2018

BACKGROUND

Rabies is a neglected zoonotic disease with a global burden of approximately 59,000 human deaths a year. Once clinical symptoms appear, rabies is almost invariably fatal; however, with timely and appropriate post-exposure prophylaxis (PEP) consisting of wound washing, vaccine, and in some cases rabies immunoglobulin (RIG), the disease is almost entirely preventable. Access to PEP is limited in many countries, and when available, is often very expensive.

METHODS

We distributed a standardized assessment tool electronically to a convenience sample of 25 low- and middle-income countries in Asia and Africa to collect information on rabies PEP procurement, forecasting, distribution, monitoring and reporting. Information was collected from national rabies focal points, focal points at the World Health Organization (WHO) country offices, and others involved in procurement, logistics and distribution of PEP. Because RIG was limited in availability or unavailable in many countries, the assessment focused on vaccine. Data were collected between January 2017 and May 2018.

RESULTS

We received responses from key informants in 23 countries: 11 countries in Asia and 12 countries in Africa. In 9 of 23 (39%) countries, rabies vaccine was provided for free in the public sector and was consistently available. In 10 (43%) countries, all or some patients were required to pay for the vaccine in the public sector, with the cost of a single dose ranging from US$ 6.60 to US$ 20/dose. The primary reason for the high cost of the vaccine for patients was a lack of funding at the central level to subsidize vaccine costs. In the remaining 4 (17%) countries, vaccine was provided for free but was often unavailable so patients were required to purchase it instead. The majority of countries used the intramuscular route for vaccine administration and only 5 countries exclusively used the dose-sparing intradermal (ID) route. Half (11/22; 50%) of all countries assessed had a standardized distribution system for PEP, separate from the systems used for routine childhood vaccines, and almost half used separate storage facilities at both central and health facility levels. Approximately half (9/22; 41%) of all countries assessed reported having regular weekly, monthly or quarterly reporting on rabies vaccination.

CONCLUSIONS

While all countries in our assessment had rabies vaccines available in the public sector to some extent, barriers to access include the high cost of the vaccine to the government as well as to patients. Countries should be encouraged to use ID administration as this would provide access to rabies vaccine for many more people with the same number of vaccine vials. In addition, standardized monitoring and reporting of vaccine utilization should be encouraged, in order to improve data on PEP needs.

Introduction of inactivated poliovirus vaccine in the Philippines: Effect on health care provider and infant caregiver attitudes and practices

BACKGROUND

The introduction of inactivated poliovirus vaccine (IPV) to the Philippines' national immunization schedule meant the addition of a third injectable vaccine at a child's 14-week immunization visit. Although previous studies have shown that providing multiple vaccines at the same time affected neither the risk of severe adverse events nor vaccine efficacy, concerns were raised that providing three injections at a single visit, with two injections in one leg, might be unacceptable to health care providers (HCP) and infant caregivers.

METHODS

We conducted pre- and post-IPV introduction surveys on the acceptance and acceptability of the additional injectable vaccine in three of the Philippines' 17 administrative regions. Regions 3 and 6 were included in the pre-introduction phase and Regions 3, 6 and 10 were included in the post-introduction phase. Thirty public health centers (PHCs) were randomly sampled from each region. HCPs and infant caregivers were interviewed. In addition, vaccination records from a minimum of 20 eligible children pre-introduction and 10 children post-introduction per PHC were reviewed.

RESULTS AND DISCUSSION

We interviewed 89 HCPs and 286 infant caregivers during the pre-introduction phase and 137 HCPs and 455 caregivers during the post-introduction phase. Among 986 vaccination records reviewed post-introduction, 84% (n = 826) of children received all three recommended injections at one visit, with a range from 61% (209/342) in Region 10 to 100% (328/328) in Region 3. The proportion of HCPs reporting that they had administered three or more injectable vaccines and the proportion of caregivers that would be comfortable with their child receiving three or more injectable vaccines at one visit increased from pre- to post-introduction (p < 0.0001 for both). Eighty-seven percent of HCPs that had administered three or more injectable vaccines post-introduction reported being comfortable or very comfortable with the number of vaccines they had administered.

Noninvasive vaccination against infectious diseases

The development of a successful vaccine, which should elicit a combination of humoral and cellular responses to control or prevent infections, is the first step in protecting against infectious diseases. A vaccine may protect against bacterial, fungal, parasitic, or viral infections in animal models, but to be effective in humans there are some issues that should be considered, such as the adjuvant, the route of vaccination, and the antigen-carrier system. While almost all licensed vaccines are injected such that inoculation is by far the most commonly used method, injection has several potential disadvantages, including pain, cross contamination, needlestick injury, under- or overdosing, and increased cost. It is also problematic for patients from rural areas of developing countries, who must travel to a hospital for vaccine administration. Noninvasive immunizations, including oral, intranasal, and transcutaneous administration of vaccines, can reduce or eliminate pain, reduce the cost of vaccinations, and increase their safety. Several preclinical and clinical studies as well as experience with licensed vaccines have demonstrated that noninvasive vaccine immunization activates cellular and humoral immunity, which protect against pathogen infections. Here we review the development of noninvasive immunization with vaccines based on live attenuated virus, recombinant adenovirus, inactivated virus, viral subunits, virus-like particles, DNA, RNA, and antigen expression in rice in preclinical and clinical studies. We predict that noninvasive vaccine administration will be more widely applied in the clinic in the near future.

Cold-Chain Adaptability During Introduction of Inactivated Polio Vaccine in Bangladesh, 2015

Background.

Introduction of inactivated polio vaccine creates challenges in maintaining the cold chain for vaccine storage and distribution.

Methods.

We evaluated the cold chain in 23 health facilities and 36 outreach vaccination sessions in 8 districts and cities of Bangladesh, using purposive sampling during August–October 2015. We interviewed immunization and cold-chain staff, assessed equipment, and recorded temperatures during vaccine storage and transportation.

Results.

All health facilities had functioning refrigerators, and 96% had freezers. Temperature monitors were observed in all refrigerators and freezers but in only 14 of 66 vaccine transporters (21%). Recorders detected temperatures >8°C for >60 minutes in 5 of 23 refrigerators (22%), 3 of 6 cold boxes (50%) transporting vaccines from national to subnational depots, and 8 of 48 vaccine carriers (17%) used in outreach vaccination sites. Temperatures <2°C were detected in 4 of 19 cold boxes (21%) transporting vaccine from subnational depots to health facilities and 14 of 48 vaccine carriers (29%).

Conclusions.

Bangladesh has substantial cold-chain storage and transportation capacity after inactivated polio vaccine introduction, but temperature fluctuations during vaccine transport could cause vaccine potency loss that could go undetected. Bangladesh and other countries should strive to ensure consistent and sufficient cold-chain storage and monitor the cold chain during vaccine transportation at all levels.

Addressing the Challenges and Opportunities of the Polio Endgame: Lessons for the Future

The Global Commission for the Certification of the Eradication of Poliomyelitis certified the eradication of type 2 poliovirus in September 2015, making type 2 poliovirus the first human pathogen to be eradicated since smallpox. The eradication of type 2 poliovirus, the absence of detection of type 3 poliovirus worldwide since November 2012, and cornering type 1 poliovirus to only a few geographic areas of 3 countries has enabled implementation of the endgame of polio eradication which calls for a phased withdrawal of oral polio vaccine beginning with the type 2 component, introduction of inactivated poliovirus vaccine, strengthening of routine immunization in countries with extensive polio resources, and initiating activities to transition polio resources, program experience, and lessons learned to other global health initiatives. This supplement focuses on efforts by global partners to successfully launch polio endgame activities to permanently secure and sustain the enormous gains of polio eradication forever.

Administering Multiple Injectable Vaccines During a Single Visit-Summary of Findings From the Accelerated Introduction of Inactivated Polio Vaccine Globally

Background.

In 2013, the World Health Organization’s (WHO’s) Strategic Advisory Group of Experts (SAGE) recommended that all 126 countries using only oral polio vaccine (OPV) introduce at least 1 dose of inactivated polio vaccine (IPV) into their routine immunization schedules by the end of 2015. In many countries, the addition of IPV would necessitate delivery of multiple injectable vaccines (hereafter, “multiple injections”) during a single visit, with infants receiving IPV alongside pentavalent vaccine (which covers diphtheria, tetanus, and whole-cell pertussis; hepatitis B; and Haemophilus influenzae type b) and pneumococcal vaccine. Unanticipated concerns emerged from countries over acceptability of multiple injections, sites of administration, and safety. We contextualized the issues surrounding multiple injections by documenting concerns associated with administration of ≥3 injections, existing evidence in the published literature, and findings of a systematic review on administration practices and techniques.

Methods.

Concerns associated with multiple-injection visits were documented from meetings and personal communications with immunization program managers. Published literature on the acceptability of multiple injections by providers and caregivers was summarized, and a systematic review of the literature on administration practices was completed on the following topics: spacing between injection sites (ie, vaccine spacing), site of injection, route of injection, and procedural preparedness. WHO and United Nations Children’s Fund data from 2013–2015 were used to assess multiple-injection visits included in national immunization schedules.

Results.

Healthcare provider and caregiver attitudes and practices indicated concerns about infant pain, potential adverse effects, and uncertainty about vaccine effectiveness with multiple-injection visits. Published literature reinforced the record of safety and acceptance of the recommended schedule of IPV by the SAGE, but the evidence was largely from developed countries. Parental acceptance of multiple injections was associated with a positive provider recommendation to the caregiver. Findings of the systematic review identified that the intramuscular route is preferred over the subcutaneous route for vaccine administration and that the vastus lateralis muscle is preferred over the deltoid muscle for intramuscular injections. Recommendations on vaccine spacing and procedural preparedness were based on practical necessities, but comparative evidence was not identified. During 2013–2015, 85 countries added IPV to their immunization schedules, 46 (55%) of which adopted a schedule resulting in 3 injectable vaccines being administered in a single visit.

Conclusion.

The multiple-injection experience identified gaps in guidance for future vaccine introductions. Global partner organizations quickly mobilized to assess, document, and communicate the existing global experience on multiple-injection visits. This evidence-based approach provided reassurance to opinion leaders, health workers, and professional societies, thus encouraging uptake of IPV as a second or third injection in an accelerated manner globally.